It was last December when Houston Texans quarterback Tom Savage fell backward in his own end zone after a hit against the San Francisco 49ers, and his helmet collided hard with the turf. That, in itself, was a red flag. Or should have been. Swift impact, helmet-to-turf, is a warning of a possible concussion.

The official was standing right there. Head coach Bill O’Brien was perched on the sideline. So was the Texans’ medical staff. A trained spotter was in the press box. Still, Savage went in on the next series.

He was eventually pulled from the game and diagnosed with a concussion. Savage didn’t play the rest of the season and he is now a signee of the New Orleans Saints.

The league also defined “seizure and fencing responses” as “No-Go” and decreed all players “demonstrating gross or sustained vertical instability” must undergo exams.

To the NFL’s credit, it acted quickly to amend its error. More cynically, this was like saying that a guy driving on the interstate while staring at his phone is showing signs of distracted driving. Seizure and fencing responses are no-go to begin with.

During the offseason, the league added a third unaffiliated neurotrauma consultant (UNC) for each game. Going forward, there will be one UNC on each sideline and another in the spotters’ booth monitoring broadcast video and audio feeds. Their role will be to notify on-field UNCs of possible head, neck or spine injuries. The UNC in the booth can advise two spotters, whose job is to alert officials on the field of the need for a medical timeout.

“We learned last year through the Savage case where after a delay, the broadcast showed additional views that hadn’t been seen,” explained Allen Sills, the NFL’s chief medical officer. “We wanted to make sure our doctors on the sidelines have all access. We wanted an extra layer for redundancy.”

Can decisions be made in time?

The thornier issue going forward isn’t new: players are going to hide their symptoms. They will scramble to their feet and say they’re fine.

These decisions have to be made quickly. There is always a next play coming up. Will the spotter or the medical staff truly be able to stop the game and remove a star player when it’s not an obvious concussion situation? It’s hard enough to decipher what a catch is in real time. How hard will it be to make a snap judgment on “gross or sustained vertical instability?”

Last season there were six medical timeouts called, one of which came in the preseason.

The NFL cares about this. This is not window dressing. But does the NFL care enough to protect its stars even against their own in-game choices and the decisions of coaches? Eventually, a team will lose a big game because a key player is removed for safety. The reaction to that, particularly from fans, will be a test for the entire league.

The good news is the NFL is more prepared for that test than it was when Savage returned to that December game.